1. Field of the Invention
The present invention relates to a sheet-like member cleaning device for removing dust particles from a sheet-like member that is fed by a feed system, and a radiation image information reading apparatus which incorporates such a sheet-like member cleaning device.
2. Description of the Related Art
A system is known for recording radiation image information of a subject such as a human body with a stimulable phosphor, and reproducing the recorded radiation image information on a photosensitive medium such as a photographic film, or displaying the recorded radiation image information on a display device such as a CRT or the like.
The stimulable phosphor is a phosphor which, when exposed to an applied radiation (X-rays, xcex1-rays, xcex3-rays, electron beams, ultraviolet radiation, or the like), stores a part of the energy of the radiation, and, when subsequently exposed to applied exciting rays such as visible light, emits light in proportion to the stored energy of the radiation. Usually, a sheet provided with a layer of the stimulable phosphor is used as a stimulable phosphor sheet.
The above known system includes a built-in radiation image information reading apparatus which comprises an imaging unit for recording the radiation image information of a subject on a stimulable phosphor sheet, a reading unit for photoelectrically reading the recorded radiation image information from the stimulable phosphor sheet by applying exciting light to the stimulable phosphor sheet, and an erasing unit for erasing remaining radiation image information from the stimulable phosphor sheet after the radiation image information has been read from the stimulable phosphor sheet. The stimulable phosphor sheet is circulated or moved back and forth in the radiation image information reading apparatus.
Another radiation image information reading apparatus for use in the above system comprises a loading unit for loading therein a cassette or a magazine which houses a stimulable phosphor sheet with the radiation image information of a subject recorded thereon, a reading unit for photoelectrically reading the recorded radiation image information from the stimulable phosphor sheet by applying exciting light to the stimulable phosphor sheet that is removed from the loading unit, and an erasing unit for erasing remaining radiation image information from the stimulable phosphor sheet after the radiation image information has been read from the stimulable phosphor sheet.
In the above radiation image information reading apparatus, the image information read from the stimulable phosphor sheet is liable to suffer an error due to dust particles or foreign matter introduced via the feed system into the reading unit or applied to the stimulable phosphor sheet. Specifically, when dust particles or foreign matter is introduced via the feed system into the reading unit or applied to the stimulable phosphor sheet, it is also read as an image, and makes it difficult for the desired image information to be read accurately. Another problem is that the introduced or applied dust particles or foreign matter causes the feed system to vibrate, and the vibration is transmitted to the reading unit, tending to blur the image read from the stimulable phosphor sheet.
It is a general object of the present invention to provide a sheet-like member cleaning device for reliably preventing dust particles or foreign matter from entering a feed system for feeding a sheet-like member.
Another object of the present invention is to provide a radiation image information reading apparatus which is capable of reliably preventing dust particles or foreign matter from entering a reading unit to allow the reading unit to read highly accurate image information from a sheet-like member.
Still another object of the present invention is to provide a radiation image information reading apparatus which has means for preventing dust particles floating or deposited in a casing from being applied again to a sheet-like member.
The above and other objects, features, and advantages of the present invention will become more apparent from the following description when taken in conjunction with the accompanying drawings in which preferred embodiments of the present invention is shown by way of illustrative example.